1. Field of the Invention
The present invention relates to a seat belt electromagnetic lock for use in connection with seat belt retractor. The seat belt electromagnetic lock has particular utility in connection with an electrically actuatable locking mechanism for locking a seat belt retractor to prevent withdrawal of seat belt webbing.
2. Description of the Prior Art
Seat belt electromagnetic locks are desirable for preventing serious injury in the event of a traffic accident. News sources tell us that approximately fifty thousand people are killed in traffic accidents each year, many occur due to side impacts and some occur due to untensioned seat belts. Current seat belt designs only work properly if the belt is tensioned around the individual, due to intermittent locking a tension eliminator device was added to seat belts. If the tension eliminator is misused and a belt is pulled out more than necessary then it becomes ineffective. A need was felt to remove the tension eliminator while ensuring a good seat belt fit. Current seat belt designs also do not adequately address the need for side impact protection. Therefore the new design was made to meet both needs, a safe comfortable seat belt fit, and protection in the event of a side impact.
The use of seat belt retractor is known in the prior art. For example, U.S. Pat. No. 3,797,603 to Loomba discloses an electromagnetically controlled seat belt retractor that is a reel type retractor for a safety belt having the feature that an electromagnet, normally activated and holds a cam member by virtue of an armature attached thereto. This armature maintains a pawl out of latching engagement with the reel, thereby permitting free engagement with the reel, thereby permitting free extension of the belt. Any interruption of the current to the electromagnet permits the reel to rotate the cam, releasing a cam follower attached to the pawl bar, and allowing the biased pawl bar to rotate into locking engagement with the reel. However, the Loomba '603 patent does not include a locking wheel which has cylindrical locking bores, nor does it have cylindrical locking pins which fit within the locking bores, nor does it have a locking key that holds the locking pin within the locking bore, nor does it include a seat belt attached at the bottom central part of the seat, with the belt divided into two parts near the top of the back of the seat with one section extending downward over each side of the front of the seat.
Similarly, U.S. Pat. No. 4,895,317 to Rumpf et al discloses an electrically actuatable locking mechanism for a seat belt retractor that comprises a spindle having seat belt webbing wound thereon. The spindle is supported for the rotation in belt withdrawal and belt retraction directions. A member is moveable between a first position in which the spindle is free to rotate in the belt withdrawal direction a second position in which the spindle is blocked from rotating in the belt withdrawal direction. A permanent magnet is fixed to the member. An energizable electromagnet includes a core locate adjacent the permanent magnet for attracting the permanent magnet for attracting the permanent magnet to thereby move the member to one of its first and second positions when the electromagnet is de-energized. The core repels the permanent magnet to thereby move the member to the other one of its first and second positions upon energization of said electromagnet. However, the Rumpf et al '317 patent does not include a locking wheel which has cylindrical locking bores, nor does it have cylindrical locking pins which fit within the locking bores, nor does it have a locking key that holds the locking pin within the locking bore, nor does it include a seat belt attached at the bottom central part of the seat, with the belt divided into two parts near the top of the back of the seat with one section extending downward over each side of the front of the seat.
Lastly, U.S. Pat. No. 4,427,216 to Kato et al discloses a seat belt tensioning device that comprises a cylinder, a piston that is slidably inserted within the cylinder. A rod connects the piston and the seat belt. A piston pushing means is provided within the cylinder for applying driving force to the piston. A trigger means comprises a plurality of rings and balls interposed between opposing rings. The trigger means is provided in the cylinder for usually locking the rod into the cylinder overcoming the driving force of the piston pushing means and releasing the rod from the cylinder to allow the movement of the piston only at an urgent time. A driving means drives the trigger means to release the rod from the cylinder at an urgent time. However, the Kato et al '216 patent does not include a locking wheel which has cylindrical locking bores, nor does it have cylindrical locking pins which fit within the locking bores, nor does it have a locking key that holds the locking pin within the locking bore, nor does it include a seat belt attached at the bottom central part of the seat, with the belt divided into two parts near the top of the back of the seat with one section extending downward over each side of the front of the seat.
While the above-described devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not describe a seat belt electromagnetic lock that allows an electrically actuatable locking mechanism for locking a seat belt retractor to prevent withdrawal of seat belt webbing. The Loomba '603, Rumpf et al '317, and Kato et al '216 patents make no provision for including a locking wheel which has cylindrical locking bores, nor do they have cylindrical locking pins which fit within the locking bores, nor do they have a locking key that holds the locking pin within the locking bore, nor do they include a seat belt attached at the bottom central part of the seat, with the belt divided into two parts near the top of the back of the seat with one section extending downward over each side of the front of the seat.
Therefore, a need exists for a new and improved seat belt electromagnetic lock that can be used for an electrically actuatable locking mechanism for locking a seat belt retractor to prevent withdrawal of seat belt webbing. In this regard, the present invention substantially fulfills this need. In this respect, the seat belt electromagnetic lock according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of an electrically actuatable locking mechanism for locking a seat belt retractor to prevent withdrawal of seat belt webbing.